This invention relates to a single-hand folding device. More particularly, it relates to a single-hand folding device of a foldable frame which can be easily folded with one hand.
For the sake of minimizing the physical volume of baby carriage to facilitate its carrying, e.g. putting it into the trunk to carry by a car, foldable carriages are desired and have been available in the related products. These foldable carriages are often designed to have a locking means so that a firm structure can be sustained after being unfolded for use. One design of the locking means is a trigger-type slidable means which is arranged to be adjacent to the joint portions of the handle frame. When the user wants to fold such kind of foldable carriages, he or she should lower his or her body so as to have two hands simultaneously approach to the trigger-type slidable means, and then press the triggers to release the locking status. Accordingly, these kinds of foldable carriages are somewhat inconvenient in use. In an improved design, a single-hand folding device which has a locking button is arranged at the top portion of the handle frame of the carriage to cooperate with the locking means. To fold this kind of carriage into itself, the user may use one of his or her thumbs to push the locking button and twist the single-hand folding device to draw up two internal wires at both side so that the two internal wires would pull the slidable locking means arranged near the joint portions to a released position. With this single-hand folding device, one may use a single hand to release the locking status of the locking means. However, there are still drawbacks existing in this kind of single-hand folding device. For example, if the locking button is arranged at the left side of the single-hand folding device, it is only suitable to operate this means by right hand, while if the locking button is arranged at the right side, only left hand is available. In addition, the twisting motion is harder for people whose wrists are not so agile.
Based on the above aspect, the purpose of this invention is to provide a single-hand folding device which can be easily operated by one single hand and meets the requirements of ergonomics in operation.
To achieve the above purpose, this invention provides a single-hand folding device comprising a slidable pressing means having racks, drawing cams having teeth on their peripheries, slidable keys for performing a locking operation and wires with one end fixed to the drawing cams and another end fixed to the slidable keys, wherein as the slidable pressing means is displaced with respect of the drawing cams, the racks of the slidable pressing means drive the drawing cams to rotate and the rotating drawing cams draw the wires to pull the slidable keys up to an opening position.
In the single-hand folding device according to this invention, a spring is further arranged at the center portion of the slidable pressing means so that a force can be exerted during pressing the slidable pressing means.
In the single-hand folding device according to this invention, the contour of the drawing cams comprises two or more arcs with different diameters, the teeth portion is configured on the arc with smaller diameter and the arc with larger diameter is used to guide the drawn wire.
These and other objects, features and advantageous of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings.